Syntheses, structures and magnetic properties of Mn(II) containing 3D polymeric networks

• Published in: Polyhedron 2007-10, Vol.26 (17), p.5113-5119
• Main Authors: Ove Kongshaug, Kjell, Fjellvåg, Helmer
• Format: Article
• Language: English
• Subjects: Coordination polymers; Magnetic properties; Single crystal X-ray diffraction; Solvothermal synthesis; Thermal properties
• ISSN: 0277-5387
• DOI: 10.1016/j.poly.2007.07.045

Two novel coordination polymers based on Mn(II) have been prepared, and their crystal structures have been solved by single crystal X-ray diffraction. Thermal and magnetic properties are discussed. Two novel 3D coordination polymers {[Mn(aip)(DMF)]} n , CPO-9, and {[Mn 3(Hatp) 2(atp) 2](H 2O) 2(DEF) 4} n CPO-10 (aip = 5-aminoisophthalate, atp = 2-aminoterephthalate, DMF = dimethylformamide, DEF = diethylformamide) have been synthesized by solvothermal methods. Their properties have been studied by single-crystal X-ray diffraction, thermogravimetric analysis, high-temperature powder X-ray diffraction and magnetic susceptibility measurements. The crystal structure of CPO-9 is based on infinite chains of carboxylato-bridged five-coordinated Mn(II) ions that are crosslinked via the aip ligands to form a 3D structure. CPO-10 is based on linear trinuclear building units of carboxylato-bridged octahedral Mn(II) ions that are crosslinked by the atp ligands into a 3D structure. Both compounds have 1D channels that contain solvent molecules. The solvent accessible void volume for CPO-10 is 51.9% of the unit cell volume. For both compounds, however, the solvent molecules cannot be removed without the collapse of the structures into amorphous phases at 250 °C. The magnetic susceptibility measurements indicate antiferromagnetic couplings between the Mn(II) ions in both compounds. The magnetic data have been fitted using theoretical approaches.